Gunmen attack Pakistan's Karachi international airport

Militants armed with automatic weapons and grenades attacked Pakistan's busiest airport in the southern city of Karachi on Sunday night, forcing the suspension of all flights, a senior police official said.

Senior police official Rao Muhammad Anwar said a gun battle was underway between heavily armed militants and security personnel.

"Exchange of fire is continuing. We don't know the exact number of the attackers but suspect four to six terrorists have attacked the airport," he said.

Abid Qaimkhani, a spokesman for the Civil Aviation Authority, confirmed the attack, adding all flights had been suspended.

At least five people have been killed in the attack, according to the head of Karachi's main hospital. Dawn News said that the attack happened at the airport’s old terminal, which is usually used for special VIP flights.

Television footage showed plumes of smoke rising from the runway where planes were parked.

There has so far been no claim of responsibility, but Pakistan has been battling a homegrown Islamist insurgency for more than a decade that has claimed thousands of lives.